LOGIC AND REASON We can acquire new knowledge about the world by using reason. We constantly use reason to go beyond the immediate evidence of our senses.

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Presentation on theme: "LOGIC AND REASON We can acquire new knowledge about the world by using reason. We constantly use reason to go beyond the immediate evidence of our senses."— Presentation transcript:

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LOGIC AND REASON We can acquire new knowledge about the world by using reason. We constantly use reason to go beyond the immediate evidence of our senses.

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For Example…. You notice the pavement is wet and conclude that it has been raining the night before. or You know that Lake Geneva is a fresh water lake and sharks don’t like fresh water; therefore there cannot be any sharks in lake Geneva.

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Reason”able” Terms Premise- a statement that is assumed to be true and from which a conclusion can be drawn. Initial assumptions that we make. So if your initial assumptions (premises) are correct, you don’t need to waste your time looking for sharks in every freshwater lake because you will find none. Reason seems to give us certainty.

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Rationalism School of philosophy called rationalism, according to which reason is the most important source of knowledge. Rationalists are impressed with areas of knowledge such as logic and mathematics, which seem to be both certain and useful. Unlike their empiricist rivals, they are suspicious of knowledge based on perception on the grounds that our senses can all too easily mislead us. However, after further investigation, logic can also be misleading.

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Sounds logical….doesn’t it? We combine multiple premises together to make conclusions. We EXTRAPOLATE…. To extrapolate- To infer something unknown from something that is known.

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Are you old enough to drink in a bar in the USA? Premise 1- All ACS Students are eighteen or under. Premise 2- You are a student Conclusion/ Inference/ Extrapolation - You are under eighteen.

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Premise 1- The legal drinking age is 21 in the USA. Premise 2- People under 21 are not allowed to drink. Conclusion- You are under 21 and will not be allowed.

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Truth vs. Validity DO NOT CONFUSE THE TWO: A premise is either true or false…. Does it really exist? BUT The conclusion drawn from the premises is valid or invalid. Validity is only based on the logical sequence of the premises.

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If the conclusion is invalid, then a Fallacy has been made. Fallacy is an error in logic.

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A QUIZ T/ F --A statement may be true, but not valid. T/F --A premise may be invalid. T/ F --A conclusion may be valid, but its premises not true. T/ F --A conclusion may be based on true premises, however its conclusion is a fallacy.